Heart stabilizer

ABSTRACT

A heart stabilizer that may include a wrist which couples an end effector to a first linkage. The end effector and wrist may be inserted through an incision in the chest of a patient to assist in performing a minimally invasive coronary procedure. The wrist provides dexterity so that the end effector can be placed on the heart to stabilize the same. The end effector may include a pair of paddles that are moved between open and closed positions by a pair of manually actuated levers. The paddles may have cleats that allow sutures to be attached to the stabilizer during a minimally invasive procedure.

REFERENCE TO CROSS-RELATED APPLICATIONS

This application is a continuation-in-part of application Ser. No.411,442 filed on Oct. 1, 1999, pending, and a non-provisional ofprovisional application Ser. No. 207,737 filed on May 26, 2000.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an articulate heart stabilizer.

2. Background Information

Blockage of a coronary artery may deprive the heart of blood and oxygenrequired to sustain life. The blockage may be removed with medication orby an angioplasty. For severe blockage a coronary artery bypass graft(CABG) is performed to bypass the blocked area of the artery. CAEGprocedures are typically performed by splitting the sternum and pullingopen the chest cavity to provide access to the heart. An incision ismade in the artery adjacent to the blocked area. The internal mammaryartery is then severed and attached to the artery at the point ofincision. The internal mammary artery bypasses the blocked area of theartery to again provide a full flow of blood to the heart. Splitting thesternum and opening the chest cavity can create a tremendous trauma tothe patient. Additionally, the cracked sternum prolongs the recoveryperiod of the patient.

Computer Motion of Goleta, Calif. provides a system under the trademarkZEUS that allows a surgeon to perform a minimally invasive CABGprocedure. The procedure is performed with instruments that are insertedthrough small incisions in the patient's chest. The instruments arecontrolled by robotic arms. Movement of the robotic arms and actuationof the instrument end effectors are controlled by the surgeon through apair of handles and a foot pedal that are coupled to an electroniccontroller. When performing a coronary procedure it is desirable tostabilize the heart. A heart stabilizer can be provided to limit themovement of the heart at the surgical site to reduce the complexity ofperforming the coronary procedure. To date there has not been developeda heart stabilizer that can be used in a minimally invasive procedure. Aminimally invasive heart stabilizer must have enough dexterity to bemaneuvered within the chest cavity of the patient.

There have been developed articulate retractors that are used inopen-heart surgery. The articulate retractors have a pair of wristjoints that allow pivotally movement of a retractor relative to a handleshaft. The joints are spatially separated such that manipulation of theretractor is cumbersome and would be impractical for use in a minimallyinvasive procedure. It would therefore be desirable to provide a heartstabilizer that can be used in a minimally invasive procedure.

SUMMARY OF THE INVENTION

One embodiment of the present invention is a heart stabilizer that mayinclude a wrist, which couples an end effector to a first linkage. Theend effector and wrist may be inserted through an incision in the chestof a patient to assist in performing a minimally invasive coronaryprocedure. The end effector may be manually actuated by moving a leverof the stabilizer.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of a minimally invasivesurgical system of the present invention;

FIG. 2 is a perspective view of an embodiment of a heart stabilizer ofthe present invention;

FIG. 3 is an enlarged view of an elbow of the heart stabilizer;

FIG. 4 is an enlarged view of an end effector of the heart stabilizer;

FIG. 5 is an exploded view of the end effector;

FIG. 6 is a bottom perspective view of the end effector;

FIG. 7 is a bottom exploded view of the end effector;

FIG. 8 is a side view of the heart stabilizer;

FIG. 9 is a bottom view of the heart stabilizer;

FIG. 10 is a bottom view of the end effector;

FIG. 11 is a sectional view taken at line 11—11 of FIG. 10;

FIG. 12 is a sectional view taken at line 12—12 of FIG. 10;

FIG. 13 is a sectional view taken at line 13—13 of 25FIG. 2;

FIG. 14 is a sectional view taken at line 14—14FIG. 2;

FIG. 15 is a top view showing the heart stabilizer fastened to a heart;

FIG. 16 is a side view of the heart stabilizer fastened to the heart.

FIG. 17 is a side perspective view of an alternate embodiment of a heartstabilizer;

FIG. 18 is an exploded view of the heart stabilizer shown in FIG. 17;

FIG. 19 is a perspective view showing the heart stabilizer of FIG. 17 ina closed position.

DETAILED DESCRIPTION

Referring to the drawings more particularly by reference numbers, FIG. 1shows a system 10 that can perform minimally invasive surgery. In thepreferred embodiment, the system 10 is used to perform a minimallyinvasive coronary artery bypass graft (MI-CABG) and other anastomosticprocedures. Although a MI-CABG procedure is shown and described, it isto be understood that the system may be used for other surgicalprocedures. For example, the system can be used to suture any pair ofvessels. The system 10 can be used to perform a procedure on a patient12 that is typically lying on an operating table 14. Mounted to theoperating table 14 is a first articulate arm 16, a second articulate arm18 and a third articulate arm 20. The articulate arms 16, 18 and 20 arepreferably mounted to the table 14 so that the arms are at a samereference plane as the patient. Although three articulate arms are shownand described, it is to be understood that the system may have anynumber of arms.

The first and second articulate arms 16 and 18 each have a surgicalinstrument 22 and 24, respectively, coupled to a robotic arm 26,respectively. The third 25 articulate arm 20 has an endoscope 28 that isheld by a robotic arm 26. The instruments 22 and 24, and endoscope 28are inserted through incisions cut into the skin of the patient. Theendoscope has a camera 30 that is coupled to a television monitor 32which displays images of the internal organs of the patient. The first16, second 18, and third 20 articulate arms are coupled to a controller34 which can control the movement of the arms. The controller 34 isconnected to an input device 36 such as a foot pedal that can beoperated by a surgeon to move the location of the endoscope 28. Thesurgeon can view a different portion of the patient by depressing acorresponding button(s) of the pedal 36. The controller 34 receives theinput signal(s) from the foot pedal 36 and moves the robotic arm 26 andendoscope 28 in accordance with the input commands of the surgeon. Therobotic arms 26 may be devices that are sold by the assignee of thepresent invention, Computer Motion, Inc. of Goleta, Calif., under thetrademark AESOP. The system is also described in U.S. Pat. No. 5,657,429issued to Wang et al., which is hereby incorporated by reference.Although a foot pedal 36 is shown and described, it is to be understoodthat the system may have other input means such as a hand controller, ora speech recognition interface.

The instruments 22 and 24 of the first 16 and second 18 articulate arms,respectively, are controlled by a pair of master handles 38 and 40 thatcan be manipulated by the surgeon. The handles 38 and 40, and arms 16and 18, have a master-slave relationship so that movement of the handles38 and 40 produces a corresponding movement of the surgical instruments.The handles 38 and 40 may be mounted to a portable cabinet 42. A secondtelevision monitor 44 may be placed onto the cabinet 42 and coupled tothe endoscope 28 so that the surgeon can readily view the internalorgans of the patient. The handles 38 and 40 are also coupled to thecontroller 34. The controller 34 receives input signals from the handles38 and 40, computes a corresponding movement of the surgicalinstruments, and provides output signals to move the robotic arms andinstruments. The entire system may be a product marketed by ComputerMotion under the trademark Zeus. The operation of the system is alsodescribed in U.S. Pat. No. 5,762,458 issued to Wang et al. and assignedto Computer Motion, which is hereby incorporated by reference.

The system may also include a heart stabilizer 60 that is used toperform minimally invasive coronary procedures. The stabilizer 60 istypically inserted through an incision of the patient's chest. Thestabilizer 60 can be held by a robotic arm or a static structure (notshown).

FIGS. 2-14 show an embodiment of a heart stabilizer 60. Referring toFIGS. 2, 8 and 9, the heart stabilizer 60 may comprise a wrist 62 thatcouples an end effector 64 to a first linkage 66. The wrist 62 allowsthe end effector 64 to be moved relative to the first linkage 66. Thefirst linkage 66 may be coupled to a second linkage 68 by an elbow 70.The elbow 70 allows the first linkage 66 to be moved relative to thesecond linkage 68. The wrist 62 and elbow 70 allow the end effector 64to be accurately located within the chest cavity of a patient. Eachlinkage 66 and 68 may be a cannula with an inner longitudinal channel.

As shown in FIGS. 3 and 4 the elbow 70 and wrist 62 may have a pluralityof universal joints 72 and 74, respectively, that provide three degreesof freedom. At least two universal joints 72 of the wrist 62 may pivotabout the same plane to minimize the relative movement of one jointpivot point relative to another joint pivot point. Relative pivot pointmovement can increase the complexity of positioning the end effector 64.Likewise, two or more universal joints 74 of the elbow 70 can pivotabout the same plane.

Referring to FIGS. 5, 6, 7, 10, 11 and 12, the end effector 64 may havea pair of paddles 76 that can move relative to a gear housing 78. Eachpaddle 76 may have an opening 80 that is in fluid communication with arigid tube 82. Each rigid tube 82 may be connected to a flexible tube84. The flexible tubes 84 may be connected to a source of vacuum (notshown) that can create a vacuum pressure at the openings 80. Theflexible tubes 84 can be routed along channels 86 of the first linkage66, as shown in FIGS. 2 and 4, to minimize the profile of the stabilizer60. Although suction paddles are shown and described, it is to beunderstood that the heart stabilizer 60 may be used without a suctionsystem. Each rigid tube 84 may be connected to a gear rack 88. Each gearrack 88 can move within corresponding channels 90 of the gear housing78. The gear racks 90 may be coupled to corresponding pinion gears 92attached to two of the universal joints 72 of the wrist 62. Theuniversal joints 72 may be connected to a pair of drive shafts 94 thatextend through the first linkage 66 as shown in FIGS. 2, 3 and 4.Rotation of the drive shafts 94 will rotate the pinion gears 92 andtranslate the corresponding gear racks 88 and paddles 76 in an inward oroutward direction. The movement of the paddles 76 occurs withoutdisturbing the relative position of the end effector 64 to the firstlinkage 66. As shown in FIGS. 5, 7 and 12, the end effector 64 mayinclude a spring clip 96 that is inserted into corresponding annulargrooves 98 of the pinion gears 92 and captures the gears 92 within thegear housing 78. The end effector 64 may also have a pin 100 that isinserted into a corresponding aperture 102 of the other universal joint72 to capture the joint 72 within the gear housing 78.

As shown in FIG. 13, the heart stabilizer 60 may include a locking pin104 that can be pressed into the drive shafts 94 to prevent rotation ofthe shafts 94. Impeding shaft rotation locks the position of the wrist62, elbow 70 and paddles 76. A surgeon may lock and unlock the wrist 62,elbow 70 and paddles 76 by rotating a head 106 of the pin 104.

As shown in FIG. 14, each drive shaft 94 may have a pinion gear 106 thatis coupled to an output shaft 108 of a motor (not shown) by a pair ofcoupling gears 110. Rotation of the output shaft 108 rotates the driveshafts and moves the paddles 76. The motor is preferably reversible sothat the paddles 76 can be moved inward or outward. The motor may beconnected to the controller 34 and foot pedal 36 shown in FIG. 1. Thesurgeon can move the paddles 76 inward or outward by depressing acorresponding switch(es) of the foot pedal 36. Alternatively, the motorcan be actuated through voice recognition.

As shown in FIGS. 15 and 16, the end effector 64 and wrist 62 can beinserted into the patient's chest cavity adjacent to the heart 112. Thesurgeon can view the location of the end effector 64 relative to theheart 112 on the monitor 32 shown in FIG. 1. The surgeon can grasp thesecond linkage 66 and move the stabilizer 60 until the end effector 64is correctly located on the heart 112. The drive motor can thenactivated to move the paddles 76 to the desired location. The surgeonmay then turn the locking pin to secure the position of the stabilizer60 relative to the patient.

As shown in FIG. 16, the vacuum source may be activated to pull theheart 112 into the paddles 76. The stabilizer 60 will then preventmovement of the adjoining area of the heart while the surgeon performs acoronary procedure with the surgical instruments 22 and 24. After theprocedure is completed, the stabilizer 60 can be removed by terminatingthe vacuum and pulling the end effector 64 out of the chest cavity.

FIGS. 17 and 18 show another embodiment of a heart stabilizer 200 thatcan be manually operated. The heart stabilizer 200 includes an endeffector 202 that is coupled to a first linkage 204 by a wrist 206. Theend effector 202 may include a pair of paddles 208. The paddles 208 canbe placed onto a beating heart to stabilize the organ. The paddles 208may have cleats 210 that can anchor sutures used to perform a medicalprocedure. The sutures can be attached to open wire ends 212 of thecleats 210 during the procedure. For example, sutures are typically usedto restrict blood flow during a coronary by-pass procedure. Therestricting sutures can be anchored by the cleats 210 and paddles 208 ofthe stabilizer 200.

The wrist 206 may include an arrangement of universal joints 214 thatallow multi-axis rotation of the end effector relative to the firstlinkage 204. A single universal joint directly couples the end effector202 to the first linkage 204 to serve as a multi-axis pivot. A sequenceof two universal joints 214 couples the shaft of each paddle 208 to itsdrive shaft 216 that extends through a tube 218 of the linkage 204. Anidentical sequence of two universal joints (or double universal jointlinkage) couples each of the two drive shafts 216 to its respectivemanually actuated levers 220. The levers 220 can rotate relative to abracket 222 that is attached to the tube 218. A single universal jointcouples the bracket 222 to the first linkage 204, serving as amulti-axis pivot for the bracket 222. Rotation of the levers 220 spinsthe drive shafts 216, and rotates the paddles 208 between an openposition and a closed position. When fully open the paddles 208 contactmechanical stops which prevents further rotation of the levers 220. Atthis point the levers 220 serve as handle which the operator may use toreorient the bracket 222 assembly relative to the first linkage 204.When such rotation about the bracket 222 pivot universal joint takesplace the double universal joint linkages to each driveshaft 216 causethe driveshafts to translate axially relative to the first linkage 204.The double universal joint linkages coupling the driveshafts 216 to thepaddle shafts 208 communicate this motion to the end effector 202. Theresult is that the end effector 202 motion mimics that of the bracket222. The stabilizer 200 includes a locking pin 224 with a knob 226 thatcan be rotated by the user to lock and unlock the drive shafts 216 andthereby fix the position of the end effector 202 and paddles 208. Thelevers 220 may have openings 228 designed to receive fingers of a user.

In operation, the user rotates the levers 220 to move the paddles 208into the closed position shown in FIG. 19. The knob 226 is preferablyrotated to lock the position of the paddles 208. The stabilizer 200 canthen be inserted through a cannula and into an internal cavity of apatient. The knob 226 can be manipulated to unlock the drive shafts 216so that the levers 220 can be rotated to move the paddles 208 into anopen position. Further manipulation of the levers 220 reorients the endeffector to the desired position on the heart at which point the knob226 can be rotated to lock the position of the paddles 208. The entireinstrument is then locked in place (relative to the patient) using astatic or robotic support arm (not shown). Sutures can be anchored byattachment to the cleats 210 of the paddles 208. When the procedure iscompleted, the paddles 208 can be moved back to the closed position andthe stabilizer 200 can be pulled out of the patient.

As with the previous embodiment, this device may use paddles whichemploy suction to enhance gripping of the heart tissue. Through suitablemodification of the paddles, both embodiments may be used to implementdoubly articulating grasping instruments, scissors, clip appliers andother manual instruments. While primarily intended for endoscopic use,all of the instruments described herein are equally suitable forconventional or open surgical procedures. By directly actuating theaxial and rotary motions of the driveshafts 216 and eliminating thebracket and levers, robotic versions of all these instrument types canbe constructed.

While certain exemplary embodiments have been described and shown in theaccompanying drawings, it is to be understood that such embodiments aremerely illustrative of and not restrictive on the broad invention, andthat this invention not be limited to the specific constructions andarrangements shown and described, since various other modifications mayoccur to those ordinarily skilled in the art. For example, although themedical devices shown in FIGS. 2-14 and 17-19 has been shown anddescribed as a heart stabilizer, it is to be understood that the devicescan be used as a retractor. The paddles 76 and 208 can be used, ormodified to be used, as retractor jaws.

What is claimed is:
 1. A heart stabilizer, comprising: an end effectorhaving at least two paddles in parallel alignment with each other,wherein each paddle has a paddle shaft which has at least one bend and atip section distal to the bend; a first linkage that has a distal endand a proximal end; a wrist that couples said proximal end of firstlinkage to said end effector to allow said end effector to move betweena position parallel with said first linkage to a position oblique tosaid first linkage; and, at least two manually actuated levers, eachlever coupled to an associated paddle and said distal end of said firstlinkage, wherein actuation of each lever rotates the associated paddleso that its tip section moves toward or away from another of the atleast two paddles while maintaining parallel alignment.
 2. The heartstabilizer of claim 1, wherein said paddle includes a cleat.
 3. Theheart stabilizer of claim 1, wherein said wrist includes a firstuniversal joint.
 4. The heart stabilizer of claim 1, further comprisinga drive shaft that is coupled to said wrist and said lever.
 5. The heartstabilizer of claim 4, further comprising a locking pin that is coupledto said drive shaft.
 6. A method for applying a heart stabilizer to aheart of a patient that has a chest, comprising: providing the heartstabilizer having a first linkage, a wrist and an end effectorcomprising at least two paddles in parallel alignment with each other,wherein each paddle has a paddle shaft which has at least one bend and atip section distal to the bend; inserting at least a portion of thefirst linkage, the end effector and the wrist through an incision in thechest of the patient; and, manually moving at least two manuallyactuated levers, each lever coupled to an associated paddle and saiddistal end of said first linkage, wherein actuation of each leverrotates the associated paddle so that its tip section moves toward oraway from another of the at least two paddles while maintaining parallelalignment.
 7. The method of claim 6, further comprising attaching asuture to a cleat of the paddle.